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9ee32fea5f
At least on the platforms that have a dp aux irq and also have it enabled - vlvhsw should have one, too. But I don't have a machine to test this on. Judging from docs there's no dp aux interrupt for gm45. Also, I only have an ivb cpu edp machine, so the dp aux A code for snb/ilk is untested. For dpcd probing when nothing is connected it slashes about 5ms of cpu time (cpu time is now negligible), which agrees with 3 * 5 400 usec timeouts. A previous version of this patch increases the time required to go through the dp_detect cycle (which includes reading the edid) from around 33 ms to around 40 ms. Experiments indicated that this is purely due to the irq latency - the hw doesn't allow us to queue up dp aux transactions and hence irq latency directly affects throughput. gmbus is much better, there we have a 8 byte buffer, and we get the irq once another 4 bytes can be queued up. But by using the pm_qos interface to request the lowest possible cpu wake-up latency this slowdown completely disappeared. Since all our output detection logic is single-threaded with the mode_config mutex right now anyway, I've decide not ot play fancy and to just reuse the gmbus wait queue. But this would definitely prep the way to run dp detection on different ports in parallel v2: Add a timeout for dp aux transfers when using interrupts - the hw _does_ prevent this with the hw-based 400 usec timeout, but if the irq somehow doesn't arrive we're screwed. Lesson learned while developing this ;-) v3: While at it also convert the busy-loop to wait_for_atomic, so that we don't run the risk of an infinite loop any more. v4: Ensure we have the smallest possible irq latency by using the pm_qos interface. v5: Add a comment to the code to explain why we frob pm_qos. Suggested by Chris Wilson. v6: Disable dp irq for vlv, that's easier than trying to get at docs and hw. v7: Squash in a fix for Haswell that Paulo Zanoni tracked down - the dp aux registers aren't at a fixed offset any more, but can be on the PCH while the DP port is on the cpu die. Reviewed-by: Imre Deak <imre.deak@intel.com> (v6) Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> |
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| .. | ||
| ast | ||
| cirrus | ||
| exynos | ||
| gma500 | ||
| i2c | ||
| i810 | ||
| i915 | ||
| mga | ||
| mgag200 | ||
| nouveau | ||
| r128 | ||
| radeon | ||
| savage | ||
| shmobile | ||
| sis | ||
| tdfx | ||
| tegra | ||
| ttm | ||
| udl | ||
| via | ||
| vmwgfx | ||
| ati_pcigart.c | ||
| drm_agpsupport.c | ||
| drm_auth.c | ||
| drm_buffer.c | ||
| drm_bufs.c | ||
| drm_cache.c | ||
| drm_context.c | ||
| drm_crtc.c | ||
| drm_crtc_helper.c | ||
| drm_debugfs.c | ||
| drm_dma.c | ||
| drm_dp_helper.c | ||
| drm_drv.c | ||
| drm_edid.c | ||
| drm_edid_load.c | ||
| drm_edid_modes.h | ||
| drm_encoder_slave.c | ||
| drm_fb_cma_helper.c | ||
| drm_fb_helper.c | ||
| drm_fops.c | ||
| drm_gem.c | ||
| drm_gem_cma_helper.c | ||
| drm_global.c | ||
| drm_hashtab.c | ||
| drm_info.c | ||
| drm_ioc32.c | ||
| drm_ioctl.c | ||
| drm_irq.c | ||
| drm_lock.c | ||
| drm_memory.c | ||
| drm_mm.c | ||
| drm_modes.c | ||
| drm_pci.c | ||
| drm_platform.c | ||
| drm_prime.c | ||
| drm_proc.c | ||
| drm_scatter.c | ||
| drm_stub.c | ||
| drm_sysfs.c | ||
| drm_trace.h | ||
| drm_trace_points.c | ||
| drm_usb.c | ||
| drm_vm.c | ||
| Kconfig | ||
| Makefile | ||
| README.drm | ||
************************************************************
* For the very latest on DRI development, please see: *
* http://dri.freedesktop.org/ *
************************************************************
The Direct Rendering Manager (drm) is a device-independent kernel-level
device driver that provides support for the XFree86 Direct Rendering
Infrastructure (DRI).
The DRM supports the Direct Rendering Infrastructure (DRI) in four major
ways:
1. The DRM provides synchronized access to the graphics hardware via
the use of an optimized two-tiered lock.
2. The DRM enforces the DRI security policy for access to the graphics
hardware by only allowing authenticated X11 clients access to
restricted regions of memory.
3. The DRM provides a generic DMA engine, complete with multiple
queues and the ability to detect the need for an OpenGL context
switch.
4. The DRM is extensible via the use of small device-specific modules
that rely extensively on the API exported by the DRM module.
Documentation on the DRI is available from:
http://dri.freedesktop.org/wiki/Documentation
http://sourceforge.net/project/showfiles.php?group_id=387
http://dri.sourceforge.net/doc/
For specific information about kernel-level support, see:
The Direct Rendering Manager, Kernel Support for the Direct Rendering
Infrastructure
http://dri.sourceforge.net/doc/drm_low_level.html
Hardware Locking for the Direct Rendering Infrastructure
http://dri.sourceforge.net/doc/hardware_locking_low_level.html
A Security Analysis of the Direct Rendering Infrastructure
http://dri.sourceforge.net/doc/security_low_level.html